Sulforaphane is known to possess antimicrobial activity and the ability to inhibit carcinogenesis and tumorigenesis. It is therefore a potentially useful agent for the treatment and prevention of microbial infections and/or cancer.
Sulforaphane is found in the cruciferous vegetables such as cabbage, broccoli, broccoli sprouts, brussel sprouts, cauliflower, cauliflower sprouts, bok choy, kale, collards, arugula, kohlrabi, mustard, turnip, red raddish, and water cress. In the plant, it is present in bound form as glucoraphanin, a glucosinolate. In nature, sulforaphane is often formed from glucoraphanin following plant cell damage by an enzymatic reaction.
Various synthetic methods of producing sulforaphane are known in the art. Sulforaphane was synthesized as early as 1948 by Schmid and Karrer (Schmid H. And Karrer, P.; Helvetica Chimica Acta. 1948; 31; 6: 1497-1505). The Schmid synthesis results in a racemic mixture. Other methods of synthesising sulforaphane developed since 1948 also result in a racemic mixture.
One major problem associated with sulforaphane is its physical instability. Sulforaphane exists in the form of an unstable oil which rapidly degrades under normal conditions. This makes sulforaphane exceptionally hard to manufacture and distribute.
One approach to stabilise sulforaphane involves the formation of sulforaphane-cyclodextrin complexes. In this regard, U.S. Pat. No. 7,879,822B2, the entire contents of which are hereby incorporated by reference, describes a synthetic process for preparing sulforaphane followed by its subsequent stabilisation by the formation of a sulforaphane-cyclodextrin complex.
However, there still remains a need for processes that enable the efficient and effective isolation and purification of sulforaphane from its various natural sources.